Device for picking up and holding a plurality of substrates and an electroplating device

ABSTRACT

In order to treat solar cells in an electroplating device, they can be inserted into a grid-like or tray-like picking-up device. They are thus mechanically held and electrical contact is made with them via contacts. Instead of individual solar cells, the picking-up devices are moved with a large number of inserted solar cells through the electroplating device for treatment. Electrical contact with the solar cells is in this case made via the contacts and the frame limbs on a projecting angle section together with edge strips of the pick-up. Contact rollers rest on the edge strips and are connected to an electrical power source.

FIELD OF APPLICATION AND PRIOR ART

The invention relates to a device for receiving or holding several flatsubstrates in one plane, as well as a galvanizing or electroplatingdevice with a passage path for the substrates through a treatmentchamber, the substrates being held in an aforementioned device.

Hitherto substrates have been conveyed on conveying rollers lying in themanner of a roller conveyor in galvanizing devices for substrates, suchas for example printed circuit boards or more especially solar cells orwafers. However, this can give rise to problems in the case of verysensitive substrates, such as for example thin solar cells. Here thesubstrates can be formed from very thin silicon, which iscorrespondingly sensitive or fragile. In addition, sensitive substrateshave to be handled with extreme care, for example on introduction into agalvanizing device. In many cases this means either increased mechanicalexpenditure for the gripping devices or a decelerated handling, whichgives rise to undesired delays.

PROBLEM AND SOLUTION

The problem of the invention is to provide an aforementioned device forreceiving or holding several flat substrates, as well as a galvanizingdevice suitable for the working thereof, enabling the problems of theprior art to be avoided and permitting a more careful working andconveying of the substrates.

This problem is solved by a device having the features of claim 1 and agalvanizing device having the features of claim 13. Advantageous andpreferred developments of the invention form the subject matter of thefurther claims and are explained in greater detail hereinafter. Byexpress reference the wording of the claims is made into part of thecontent of the description.

According to the invention the device has a frame with frame piecesforming reception zones between them and as a result of the frame piecesrecesses or cutouts are formed. The frame pieces can run in grid-likemanner, particularly with an outer frame and intermediate frame piecesas subdivisions. The frame pieces have supports for the substrates onwhich the substrates rest. Thus, the mechanical holding of thesubstrates and/or an electrical contacting takes place on the substrateside engaging on the supports. In this way a reception device or holderfor several flat substrates can be created, in which the substrates areplaced in the reception zones. For various treatment steps with respectto the substrates, as well as for conveying and in certain circumstancesalso storage, there is no need to move the individual substrates andinstead the complete reception device is moved. The latter can be mademore robust than the substrates, so that it is readily possible to useconventional gripping devices or the like. As a result of the supportsthere can be a precisely defined connection between the reception deviceand the substrate, which can be matched to specific substratecharacteristics. As a result of the reception device it is possible inthe case of a plurality of substrates to not only move one substrate inconnection with individual working steps, but instead all the substratesof a reception device can be moved. If electrical contacting with thesubstrates takes place via the reception device or the supports, incertain cases it is possible to economize additional contacting devicesdirectly on the substrates. This also has the advantage that themechanical loading of the substrates by contact rollers or othercontacting devices can be reduced or avoided. Thus, advantageously thereception device brings about both a mechanical holding or reception ofthe substrates and also an electrical contacting thereon.

The supports can for example be constructed as projections, whichproject or emanate from the frame pieces. The projections can either berelatively narrow, i.e. almost punctiform, in order to bring about avery limited surface coverage on the substrates. This permits a contactwith a treatment medium in a galvanizing device in an advantageous, verylarge-area manner. Alternatively the projections can be wider in orderto bring about a type of linear supporting of the substrates with theirmarginal area on the receptacles or frame pieces. This permits anadequately stable supporting or bearing action, especially withsensitive substrates, because there is a distribution thereof. Theprojections can also run below the plane of the frame pieces, forexample by a downward bend. This makes it possible to have the bearingsubstrates in roughly one plane with the holder or the frame pieces. Itis also possible for the projections to project downwards over the planeformed by the underside of the frame pieces. Advantageously thesubstrates rest in the reception device or on the projections in such away that their top side is not below the plane of the top side of theframe pieces and instead preferably projects by a small amount. Thismakes it possible to ensure that rollers or the like engaging from abovein all cases also engage on the top side of the substrates and notmainly on the frame pieces projecting over the substrates.

For electrical contacting purposes it is possible to provide on thesupports special contacts which project upwards. Through said contacts,which are in particular fitted separately to the projections, electricalcontacting can be improved independently of the material or constructionof the projections. Contacts can be in the form of contact projections,contact points or contact studs with electrically conductive surfaces.In particular, the contacts can be made from contact materialadvantageously used for switching contacts. In a development of theinvention it is possible to provide them with seals in such a way thatno electrical contact takes place when the substrates are applied. Thus,in the case of a galvanizing process undesired deposits on the contactscan be avoided, because the treatment medium cannot come into directengagement with the contacts as a result of the seal. It is possible tohave cup or pot-shaped rubber seals around the contacts.

It is advantageous for electrical contacting if some or all the framepieces are electrically conductive. In particular the entire receptiondevice is electrically conductive and can for example be made frommetal. Advantageously all parts or frame pieces of the reception deviceare electrically conductively interconnected. For this purpose such areceptacle can be rough worked from a metal sheet in the manner of agrid-like tray.

In a further development of the invention, it is possible to provide thereception device with an electrically insulating coating, for examplepaint or a covering. This avoids any deposition of coating material onthe receptacle during a galvanizing process. If such deposition ofcoating material takes place on the aforementioned contacts as exposedsurfaces of the reception device, then at certain time intervals saidcontacts must be cleaned or stripped free, as is known to the expert.

A part or section of the device can project on an outside, particularlyan outer area or from an outside frame piece. This is advantageouslybent upwards from the plane of the substantially flat device,particularly with a further sideways bending following onto the same. Ifsaid projecting section is for example electrically conductivelyconnected to the frame pieces or electrical contacts for the engagementof the substrates, then via said section there can be an electricalcontacting with the reception device. For this purpose, the section canfor example be made from the same material as the remainder of thedevice, for example it can be rough worked from the aforementioned metalsheet. It is advantageously possible to construct the entire receptiondevice integrally or in one piece. Said section can also be used for thegripping of the reception device in an area which is remote from theinserted substrates, so as to provide protection for the same.

In a further development of the invention it is possible to constructthe reception device in such a way that a substrate is sealingly locatedin a reception zone between adjacent frame pieces. Thus, all thereception zones of a reception device carry substrates and in this wayform a substantially liquid-tight surface. The sealing or tightnessrequirements must at least be such that in the case of movement throughthe treatment medium or a liquid bath liquid does not penetrate frombelow through the areas between the substrate and the frame pieces, thisapplying in the case where the pressure of the liquid from below is onlylimited. For this purpose it is possible to have seals along the framepieces or along the areas where the substrate sides are close to theframe pieces. This makes it possible to keep the top side of thesubstrates and also the reception device free from treatment liquid.This is especially advantageous if there is to be a treatment or coatingonly on the downwardly directed side of the substrates.

Advantageously the reception device is constructed for identicalsubstrates and each substrate is then held in the same way. To this endseveral reception zones are provided successively in juxtaposed manner,for example with an overall rectangular zone.

In a further development of the invention onto the reception device canbe fixed a covering device or cover, particularly in a movable orarticulated manner. Substrates placed in the reception device can befixed by the cover or secured against dropping out or becoming detached.The cover can cover roughly the same surface area as the receptiondevice. Advantageously it has a similar structure with pieces andinterposed zones. Particularly advantageously it is constructed in asubstantially similar or almost identical manner to the receptiondevice. If the substrates are also held or secured from above in thereception device, easier movement thereof is possible and in particularcan be held vertically or even rotated. If the cover is fixed at anumber of points to the reception device, it can be made much thinner orweaker because it does not necessarily have to form an independentlysupporting structure. Its function is solely to hold the substrates inthe reception zones of the reception device.

For the inventive galvanizing device it can be provided that thesubstrates run through the treatment chamber. The latter contains atreatment medium, for example an electrolyte, for the galvanicapplication of a coating to the substrates. The substrates canadvantageously be thin printed circuit boards or alternatively thinsolar cells, as described hereinbefore. The passage path has conveyingmeans, for example conveying rollers, wheels, etc. By means of thelatter the above-described reception device is conveyed or runs on thepassage path through the treatment chamber. On the reception devices oron the substrates can engage pressure rollers, wheels or the like forvarious different functions. It is possible for there to be at least onesuch pressure roller in the passage direction for each successive row ofsubstrates. If the substrates are very sensitive, as statedhereinbefore, the pressure rollers are advantageously particularly softso as not to damage the substrates.

An aforementioned reception device projects laterally over or away fromthe substrate plane and is in particular bent upwards. The angularsection extends to an aforementioned electric contacting means and isadvantageously not in contact with the treatment medium or is positionedoutside the galvanizing device. It is particularly advantageous to bendthe reception device upwards and then to the side, so that the endprojects over the galvanizing device. Electrical contacting can takeplace through engaging contacting rollers or jointly running contactclips or other contacts, such as also contact brushes.

Advantageously the treatment medium extends to the underside of thesubstrates passing through or up to the latter. In order to keep the topof the substrates dry and clean, it is possible for the height level toextend relatively precisely to the underside of the substrates. This canlead to a type of wave formation in the treatment medium, in order thatthe underside of the substrates is reached by the weak waves or withtheir wave crests. Alternatively substrates can be placed in thereception device in sealing manner, as described hereinbefore.

Electrodes or the like for the galvanizing process can be provided belowthe substrates. If the substrates pass in fully immersed manner throughthe treatment medium, electrodes can also be provided above the same.

In another embodiment of the invention on the top side of the receptiondevice, for example between the pressure rollers, several contactingmeans can be provided forming an electrical contact with the substrates.They can be constructed as circumferential contacting rollers. For thispurpose they can engage on the frame pieces, advantageously running inthe conveying direction. It is particularly advantageous to provide atleast one contacting means on each frame piece running in the conveyingdirection.

These frame pieces, on which the contacting means engage, can beadvantageously higher than the substrates in the reception device. Thus,they are generally above the liquid bath level. They are alsoelectrically conductive. For contacting the substrates, besides anaforementioned, completely conductive frame, contact bridges can beprovided, which run from the frame pieces with the contacting means tothe substrates located therein. They can have a bow or bridge-likeconstruction and lead bilaterally from the frame pieces to thesubstrates and the substrates can rest on ends of the contact bridges.This permits electrical contacting of the substrates even withoutconductive frames.

Between in each case one pair of pressure rollers can be provided acontacting roller, preferably on the same shaft. The contacting means,preferably contacting rollers, can be constructed resiliently orelastically, particularly with contacting surfaces projectingresiliently from a solid central part. They can be segmented, but thisgenerally only serves to provide a more resilient construction.

These and further features can be gathered from the claims, descriptionand drawings and the individual features, both singly or in the form ofsubcombinations, can be implemented in an embodiment of the inventionand in other fields and can represent advantageous, independentlyprotectable constructions for which protection is claimed here. Thesubdivision of the application into individual sections and thesubheadings in no way restrict the general validity of the statementsmade thereunder.

BRIEF DESCRIPTION OF THE DRAWINGS

An embodiment of the invention is described in greater detailhereinafter relative to the attached diagrammatic drawings, whereinshow:

FIG. 1A sloping view of an inventive reception device.

FIGS. 2 & 3 Larger scale detail views of the reception device of FIG. 1.

FIG. 4 A sectional representation through an inventive galvanizingdevice for solar cells.

FIG. 5 A side view of the galvanizing device of FIG. 4.

FIG. 6 A sloping view of another inventive galvanizing device.

FIG. 7 A larger scale detail view of the contacting on the receptiondevice of FIG. 6.

DETAILED DESCRIPTION OF THE EMBODIMENT

FIG. 1 shows in a sloping or oblique view a reception device 11 which isconstructed in the manner of a tray. Outside external frame pieces 12and intermediate inside frame pieces 14 form a type of grid or latticewith recesses between them, so as to constitute reception zones 20. Itcan be seen that all the reception zones 20 between frame pieces 12 and14 are of the same size, although this need not be the case.

On the rightwards-directed side is provided an angular section 16. Herethe outside frame piece 12 is firstly bent upwards and then with amarginal strip 17 to the side again. The reception device 11 can be madefrom metal, particularly a sheet metal plate. It can be coated ininsulating manner with a covering or a paint, which is resistant to thetreatment media generally used during galvanizing. The marginal strip 17is free on at least one side or has an electrically conductive surface,advantageously this is on both sides.

Particularly the larger scale view of FIGS. 2 and 3 reveals how at anumber of points projections 22 project from the frame pieces 12 and 14.They can either be fixed subsequently to the frame pieces, for exampleby welding, or alternatively they can be rough worked by a punchingprocess or the like from a single metal sheet together with said framepieces. The sectional view of FIG. 3 shows that the thickness of theprojections 22 is less than the thickness of the frame pieces and inparticular they are only half as thick. As a result in the case of thesolar cells or silicon wafers 26 resting on contacts 24 located at theend of projections 22, as shown in broken line form in FIG. 2, the topside of the solar cells is not too far above the top side of thereception device 11 or frame pieces 12 and 14. This is explained ingreater detail hereinafter relative to FIGS. 4 and 5.

The contacts 24 can for example be contact points or tips and can bemade from a contact material normally used for switching contacts or thelike, i.e. from a different material to the projections 22. This has theadvantage of even better contacting with the solar cells 26 or othersubstrates to be placed in the reception zones 20.

In alternative developments of the invention, in place of theindividuals relatively small projections 22, wide strips project fromthe frame pieces 12 and 14 permitting a wider engagement of the solarcells and consequently a better mechanical support. It is also possibleto have more than the three projections 22 shown for each reception zone20 and they are in particular distributed over all the frame pieces. Theadvantage of a small number of projections 22 is the ease ofmanufacture. In addition, as a result the treatment medium is appliedparticularly well to the underside of the substrates or solar cells.

In a further development of the invention it is conceivable to havecircular seals or the like around the contacts 24 at projections 22 insuch a way that the contacts 24 engage on the solar cells 26 in asubstantially punctiform area. This engagement area is surrounded by theseal and shielded to the outside, the seal being as close as possible tothe contacts in order to keep the engagement area as small as possible.In this case the contacts are protected from coming into contact withthe treatment medium and are in this way not coated. The preciseconstruction of such seals is known to the expert and can be implementedwithout difficulty.

In the representation of a galvanizing device 30 in FIG. 4, walls 31form a treatment chamber 32 housing an electrolyte as a treatment mediumin which is dissolved the metal which is to be deposited on the solarcells 26. The reception devices 11 according to FIG. 1 are conveyedlying on conveying rollers 33 through the galvanizing device 30. Theconveying rollers 33 are driven by a drive 34. As can be seen in FIG. 5and as is generally known, numerous conveying rollers 33 aresuccessively arranged and form a passage path for the reception devices11 or solar cells 26.

At each reception zone 20 the reception device 11 is covered by a solarcell 26. The pressure rollers 36 engage on the top side of solar cells26 in galvanizing device 30. They comprise a very flexible rubbercovering 37 on a metal core 38 and are also driven by drive 34. Thepressure rollers 36 are positioned in such a way that they in each caserest relatively precisely centrally along the rows of successive solarcells 26. The function of the pressure rollers 36 is to hold the solarcells 26 in the reception device 11 or reception zones 20 and to ensurethe engagement of the contacts 24 on the underside.

The angular section 26 of reception device 11 projects upwards at leastover the level of the treatment medium in the treatment chamber 32. Therightwards-projecting marginal strip 17 projects over the right-handwall 31 and beyond. A contact roller 42 contacts the underside. In muchthe same way as for the conveying rollers 33 and pressure rollers 36 inFIG. 5 a plurality of contact rollers 42 is provided along the passagepath. By means thereof there is a constant electrical contact with themarginal strip 17 and consequently the reception device 11. The contactroller 42 is once again connected to a power source 44 or its negativepole. The positive pole of the power source 44 is connected to elongatedelectrodes 40, which are positioned between the rollers above and belowsolar cells 26 in treatment chamber 32.

Function

The solar cells 26 are placed in the reception device 11 for treatmentpurposes. Electrical contacting of the solar cells with the receptiondevice 11 takes place via the contacts 25 engaging with the underside.By means of a not shown covering device or the like the solar cells 26can be firmly held in the reception zones 20, for example by a further,grid-like frame, clips, etc. In a further development of the inventionsprings or the like can be provided which press the solar cells 26 intothe reception zones 20 or against the contacts 24 and are automaticallylocked on inserting the substrates. Finally, it would also be possibleto have small suction cups, a vacuum holding means, etc., for example inthe vicinity of projections 22. They can also embrace the contacts 24with the aforementioned sealing function.

The solar cells 26 are advantageously made from silicon or are siliconwafers. Hitherto they have been printed on in complicated manner in partwith silver paste as the contact material. The galvanizing device 30 isprovided to galvanically deposit the contact layer, particularly on thefront of the solar cells. Thus, the treatment medium in the treatmentchamber 32 contains a corresponding proportion of contact material, forexample silver.

The reception device 11 containing the solar cells 26 is then introducedinto the galvanizing device 30. The reception device 11 moves along thepassage path on conveying rollers 33 through said treatment chamber 32.If deposition of silver is only to take place on the underside of thesolar cells 26, the height of the treatment medium can becorrespondingly chosen or the treatment medium should only extend to theunderside of the solar cells 26.

The solar cells 26 are electrically conductively connected by theirunderside via contacts 24 and projections 22, as well as frame pieces 12and 14 with the angular section 16 or marginal strip 17. As contactrollers 42 extend up to the marginal strip 17 and are once againconnected to the negative pole of power source 44, the undersides of thesolar cells 26 are at this potential. By means of electrodes 40connected to the positive pole of power source 44, voltage is applied orthe potential gradient to the solar cells 26 is built up for thedeposition of silver from the treatment medium on the underside of solarcells 26. Process parameters, such as the passage speed and compositionof the treatment medium and the operation of the power source 44, are ineach case to be chosen as a function of the given application andprovide no problem to the expert. Following adequate silver depositionor coating, the reception device 11 with solar cells 26 is removed orextended out of the galvanizing device 30. This can be followed by afurther treatment or an intermediate storage. For as long as the solarcells 26 are not individually required or worked, they can be left inthe reception device 11. In the latter they can be easily conveyed,stored and protected against damage.

As coating material is also deposited on the reception devices 11, atleast on contacts 24 if they are unprotected, the coating is to beremoved therefrom at certain time intervals. This process is called“destripping” by the experts. It is advantageous if the reception device11 only has an electrically conductive surface in the vicinity ofcontacts 24 and marginal strip 17, because then no coating can takeplace in the remaining areas. Alternatively to the aforementionedremoval of a coating, this can take place in a wet chemical manner.

FIG. 4 shows how the pressure rollers 36 in each case press the solarcells 26 into the reception zones 20. As the top of the solar cells 26project slightly over the top of the frame pieces 12, 14, it is ensuredthat the pressure rollers 36 always engage on the substrates or solarcells 26 and consequently press the latter downwards against thecontacts 24.

In addition to the power source 44, there can also be light sourcesbelow the solar cells 26. They can assist the coating process byirradiating the solar cells 26 from below with light of a suitablewavelength, preferably in a range 400 to 1100 nm. In certaincircumstances it is even conceivable for the necessary galvanizingcurrent to be produced solely by the light sources. However,advantageously such a light-induced current generation is combined withan aforementioned, controlled power source.

In the alternative variant according to FIGS. 6 and 7, a frame-likereception device 111 with outside frame pieces 112 and inside framepieces 114 is covered with substrates 126. They are conveyed byconveying rollers 133 through a plant similar to that describedhereinbefore. Substrates 126 are held by pressure rollers 136 in thereception device 111. The pressure rollers 136 are located on the sameshafts 150 as the intermediately provided contacting rollers 152. Thelatter have resilient contact zones 154 projecting from a central part153. The contacting rollers 152 or contact zones 154 engage on the topof the frame pieces 114. The latter are continuously electricallyconductive or have a corresponding coating or support.

From said electrically conductive frame pieces 114 contact bridges 155project bilaterally. They can alternatively be in the form of clips orhave some similarly functioning shape. The contact bridges 155 pass intoends 156 on which rest the substrates 126 and are in this wayelectrically contacted in the aforementioned manner with the contacts24.

It is advantageous here that an electrical contacting on the frame takesplace in surface-distributed, central manner, i.e. not only from oneside. Thus, there are no current gradients. In the case of localcontamination on one contact surface, there is much less risk of aninterruption of the power supply. The individual current supply to allthe frame pieces 114 in the passage direction is also conceivable, iffurther measures of galvanic separation or isolation from electrolysisare carried out.

1. A device for receiving and holding several flat substrates in oneplane, said device having a frame with frame pieces forming receptionzones between them with recesses and cutouts in a vicinity of said framepieces, said frame pieces having supports for said substrates formechanically holding said substrates or for electrical contacting saidsubstrates on an engaging substrate side of said substrates.
 2. Thereception device according to claim 1, wherein said supports areprojections projecting from said frame pieces, said projections runningbelow said plane of said frame pieces in such a way that said substratesrest thereon and are roughly in one plane with said receptacle or withsaid frame pieces.
 3. The reception device according to claim 1, whereinsaid supports have upwardly projecting contact projections.
 4. Thereception device according to claim 1, wherein at least part of saidframe pieces is electrically conductive and are made from metal, whereinsaid electrically conductive frame pieces are electrically conductivelyinterconnected.
 5. The reception device according to claim 4, whereinsaid reception device and said frame pieces are largely electricallyinsulated on their surface.
 6. The reception device according to claim1, wherein said reception device is provided with a section projectingfrom an outer area of said reception device, wherein said section isbent upwards from said plane of said reception device and then to aside.
 7. The reception device according to claim 6, wherein said sectionis projecting from an outside frame piece of said reception device. 8.The reception device according to claim 6, wherein said projectingsection is electrically conductively connected to said frame pieces orsaid electrical contacting means on said engaging substrates, whereinsaid projecting section has an electrically conductive surface.
 9. Thereception device according to claim 1, wherein said reception device isintegrally constructed in one piece.
 10. The reception device accordingto claim 1, wherein one said substrate rests inserted in sealing mannerin a reception zone of said reception device between adjacent framepieces in such a way that said substrate downwardly seals againstpenetration of a liquid at low pressure between said frame pieces. 11.The reception device according to claim 10, wherein seals are providedat said frame pieces for engagement on said inserted substrate.
 12. Thereception device according to claim 1, wherein there are several saidreception zones in juxtaposed, successive manner.
 13. The receptiondevice according to claim 1, wherein a covering device is provided whichto be fixed to said reception device, wherein said inserted substratesare located between said reception device and said covering device andare secured against dropping out.
 14. The reception device according toclaim 13, wherein said covering device roughly covers a surface areathat is of similar size than that of said reception device.
 15. Agalvanizing device with a treatment chamber and a passage path forsubstrates through said treatment chamber, wherein said galvanizingdevice uses a treatment medium such as an electrolyte for galvanicapplication of a coating to said substrates, wherein said passage pathhas conveying means such as conveying rollers for horizontal conveyingof a reception device for receiving and holding several flat substratesin one plane, said device having a frame with frame pieces formingreception zones between them with recesses and cutouts in a vicinity ofsaid frame pieces, said frame pieces having supports for said substratesfor mechanically holding said substrates or for electrical contactingsaid substrates on an engaging substrate side of said substrates throughsaid passage path.
 16. The galvanizing device according to claim 15,wherein pressure rollers are provided engaging from above on saidreception devices or said substrates, wherein there is at least one saidpressure roller for each successive row of said substrates in adirection of said passage path, wherein said pressure rollers areconstructed in flexible manner.
 17. The galvanizing device according toclaim 15, wherein said reception device is provided with a sectionprojecting from an outer area of said reception device, wherein saidsection is bent upwards from said plane of said reception device andthen to a side, and projects upwards with a lateral angular section awayfrom a plane of said substrates and extends to an electrical contactingmeans with a further intermediate horizontal bend.
 18. The galvanizingdevice according to claim 17, wherein said electrical contacting meanshas contact rollers engaging on said projecting section.
 19. Thegalvanizing device according to claim 15, wherein a height level of saidtreatment medium extends just up to an underside of said substrateslocated in said reception device.
 20. The galvanizing device accordingto claim 15, wherein there are several contacting means on top of saidreception device between said pressure rollers.
 21. The galvanizingdevice according to claim 20, wherein said contacting means areconstructed as circumferential contacting rollers having an electricalcontact with said substrates.
 22. The galvanizing device according toclaim 20, wherein said contacting means engage on frame pieces runningin a conveying direction of said galvanizing device, wherein at leastone contacting means engages on each said frame piece running in saidconveying direction.
 23. The galvanizing device according to claim 22,wherein said frame pieces are higher than a level of said substrates insaid reception device.
 24. The galvanizing device according to claim 22,wherein electric contact bridges run from said frame pieces, on whichsaid contacting means engage, up to said substrates located in saidreception device in bilateral and bow-like manner away from said framepieces to said substrates, wherein said substrates rest on ends of saidcontact bridges.
 25. The galvanizing device according to claim 22,wherein a contacting roller is provided between each pair of pressurerollers on the same shaft.
 26. The galvanizing device according to claim22, wherein said contacting means are constructed in resilient mannerwith contacting surfaces projecting resiliently from a solid centralpart of said contacting means.